Fiber cement composite siding is a high quality building material having many advantages over vinyl, aluminum or wood siding. One major advantage is the significantly better durability of fiber cement siding. Fiber cement siding typically includes a substrate made from wood pulp or synthetic fiber mixed with a binder that includes silica, hydraulic cement and water. The mixture is pressed, cast, molded, roll-formed, extruded or otherwise formed into a green board form and dried. One or both major surfaces of the siding may be profiled or embossed to look like a grained or roughsawn wood or other building product, or scalloped or cut to resemble shingles. A variety of styles or shapes (including lap siding, vertical siding, soffit panels, trim boards, shaped edge shingle replicas and stone or stucco replicas) are available in a variety of sizes and thicknesses. Fiber cement siding may be prefinished (e.g., primed or painted) at the factory where it is made and delivered to a job site ready for installation (viz., attachment) on a building. The resulting prefinished siding product has a primed or painted appearance immediately upon attachment.
Unfortunately, some finishes adhere poorly to fiber cement siding products, especially near edges and corners. An applied finish may initially appear to be properly adhered but may later delaminate or otherwise prematurely fail once the product has been stored, stacked or transported, during product installation, or even after the product has been installed. While builders and homeowners desire the beauty and convenience of fiber cement siding, premature finish failure can defeat the purpose of manufacturing boards with a preapplied finish.
From the foregoing, it will be appreciated that what is needed in the art is a prefinished fiber cement siding product with improved coating adhesion and a reduced tendency to exhibit premature finish failure, especially near edges and corners. Such siding products and methods for preparing the same are disclosed and claimed herein.